1. We have previously developed a method to totally clean the lumen of the tracheal tube in intubated sheep thorough the use of a catheter tip mounted inflatable balloon, provided with two "Shaving Rings"; upon inflation and retrieval of the Mucus Shaver, all mucus within the tracheal tube is removed in one sweep. 2. Now undergoing late stage test/evaluation is a novel system that, when implemented, is capable to maintain the tracheal tube, and the trachea free of mucus, and free of bacterial colonization; with no need for tracheal, or tracheal tube suctioning. 3. Based on above studies, and our preceeding studies, a clinical study is to be conducted headed by a former Visiting Fellow (Dr. Lorenzo Berra), in collaboration with PCCM, to evaluate clinical benefits of 1.The mucus shaver and 2. Tracheal tubes coated with silver sulfadiazine in polyhurethane. Such clinical protocol has been approved by the IRB of the participating hospital administration in Italy, and by the NHLBI IRB. The patient population is to consist of both patients in the medical ICU; and cardiosurgical patients